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Abstract Filamentary structures are ubiquitous in the interstellar medium, yet the extent to which magnetic fields influence the morphology of cold atomic gas remains an open question. The nearby Riegel–Crutcher cloud, composed of long and narrow Hifilaments observed in self-absorption, provides a critical test case. We present the most extensive optical polarimetric survey of this region to date, comprising more than 90,000 high signal-to-noise stellar polarization measurements combined with Gaia DR3 data. Using stellar polarization, extinction estimates, and archival Naiabsorption data, we locate the cloud at a distance of 150  ±  15 pc, consistent with that of the Pipe Nebula. The plane-of-sky magnetic field traced by optical starlight polarization closely matches that inferred independently from Planck 353 GHz dust-emission polarization, revealing a coherent large-scale magnetic field across the region. A Rolling Hough Transform analysis shows that the Hifilaments are tightly aligned with this field orientation. Together, these results provide strong observational evidence that the structure of the cold neutral medium in the Riegel–Crutcher cloud is closely linked to a highly ordered magnetic field. This level of coherence supports a scenario in which magnetic fields play a dynamically important role in shaping the cloud structure, and suggests that the Riegel–Crutcher cloud is part of a larger magnetized complex influencing gas flows in the solar neighborhood. 

Accurate first-principles prediction of lattice thermal conductivity (κL) remains challenging in identifying materials with extreme thermal behavior. While the harmonic approximation with three-phonon scattering (HA + 3ph) is now routine, reliable κL prediction often requires higher-order anharmonic effects, including self-consistent phonon renormalization, three- and four-phonon scattering, and off-diagonal heat flux (SCPH + 3, 4ph + OD). We present a state-of-the-art high-throughput workflow that unifies these effects and apply it to 773 cubic and tetragonal crystals spanning diverse chemistries and structures. From 562 dynamically stable compounds, we assess the hierarchical impacts of higher-order anharmonicity. For around 60% of materials, HA + 3ph predictions closely match those from SCPH + 3, 4ph + OD. SCPH generally increases κL, by over 8 times in extreme cases, whereas four-phonon scattering universally suppresses κL, sometimes to 15% of the HA + 3ph value. Off-diagonal contributions are negligible in high-κL systems but can rival diagonal terms in highly anharmonic low-κL compounds. We highlight four case studies, Rb2TlAlH6, Cu3VSe4, CuBr, and KTlCl4, that exhibit distinct extreme behaviors. This work delivers not only a robust workflow for high-fidelity κL dataset but also a quantitative framework to determine when higher-order effects are essential. The hierarchy of κL results, from the HA + 3ph to SCPH + 3, 4ph + OD level, offers a scalable, interpretable route to discovering next-generation extreme thermal materials. 

Abstract The dust continuum emission from young protostellar disks encodes key information about their mass distribution and early evolution, yet uniform high-resolution comparative studies remain limited. We present a systematic uv-plane analysis of parametric intensity models applied to Atacama Large Millimeter/submillimeter Array (ALMA) Band-6 (1.3 mm) observations of 23 disks (19 protostellar systems, with four being in binary) from the eDisk sample, spanning Gaussian profiles to power-law cores with exponential tails (PLCT), including asymmetric extensions. Gaussian models generally fail to reproduce the centrally peaked emission and extended outer structure observed in most disks, whereas the PLCT framework provides a significantly improved description of radial brightness profiles. Incorporating azimuthal asymmetries further reduces residuals in 15 of 17 inclined disks, indicating that departures from axisymmetry are common at early stages. Only two disks, L1489 IRS and Oph IRS63, exhibit clear gap and ring substructures, while most appear smooth at the spatial resolution and sensitivity of our observations. These systems are among the most evolved in the sample, and the absence of flat-spectrum sources limits the evolutionary range probed, suggesting that the detection of prominent gaps and rings is not common in the earliest phases of disk evolution. Using a uniform definition of disk radius based on the 95% enclosed flux, we find a positive correlation with stellar mass, $R_{\mathrm{disk}}\propto M_{\star }^{1.5\pm 0.1}$ , with disks in binary systems systematically smaller than those around isolated protostars. While the models capture overall morphology and large-scale asymmetries, distinguishing intrinsic structures from radiative transfer effects in optically thick regions remains challenging. 

Abstract Recent James Webb Space Telescope observations of Hii regions in the Central Molecular Zone (CMZ) have shown a highly filamentary morphology distinct from Hii regions in other parts of the Galaxy. We present magnetohydrodynamic (MHD) simulations of strongly magnetized (plasma-β ≪ 1) Hii region evolution that investigate and describe the formation of these ionized gas filaments. Hii region evolution has been simulated in a 30 pc³box, in distinct models with preplaced overdensities in the ambient medium and overdensities that have been generated with driven turbulence. We find that when these overdensities are seeded in the ambient medium before the birth of the ionizing source, the photoionized plasma stripped off of these dense blobs is funneled into long filaments along the magnetic field lines. The length and emission measure of these ionized gas filaments are similar to the filaments observed in the CMZ. Given that these filaments are effectively magnetically confined flows of photoionized gas, their density and curvature are influenced by the density of the blob and the geometry of the configuration. 

Abstract (Sub)millimeter dust polarization in protoplanetary disks has revealed the presence of large (∼100 μm) dust grains that are aligned along their long axis following the azimuthal direction of the disk. The novel badminton-birdie-like aerodynamic alignment predicts large grains to align with their long axes following the direction of gas flow experienced by the dust, denoted as theA-field. With 3D streaming instability (SI) simulations, we find that theA-field is predominantly in the radial direction in regions of low dust-to-gas ratio but in the azimuthal direction in regions of high dust-to-gas ratio. Through polarized radiation transfer, we find that the resulting polarization angle indeed follows the disk azimuthal direction in the high dust density regions. Therefore, ongoing SI is an attractive candidate for producing the azimuthal dust polarization pattern as observed in an increasing number of disks. 

Abstract The origin of the jets in young stellar objects (YSOs) remains a subject of active investigation. We present a 3D MHD simulation of the jet launching in YSOs, focusing on the interaction between the stellar magnetosphere and the accretion disk. In our model, a fast low-density bipolar jet is powered by disk–magnetosphere interaction and launched through the polar cavity that is mass-loaded from the disk rather than the star. Specifically, outflows are driven by toroidal magnetic pressure generated along “two-legged” field lines, anchored at a magnetically dominated stellar footpoint and a mass-dominated point on the (magnetically elevated) disk surface via a cyclic “load–fire–reload” process: in the “load” stage, the differential rotation between the stellar and disk footpoints generates toroidal magnetic pressure; in the “fire” stage, vertical gradients in the toroidal field accelerate plasma and transport the Poynting flux into the polar cavity; and in the “reload” stage, magnetic reconnection allows the cycle to repeat, reforming “two-legged” field lines. These field lines are not required to be fully reset to a dipolar loop configuration; it is only required that the disk end be shallowly embedded in the (elevated) disk surface. This rapid asynchronous process produces a continuous large-scale outflow. The resulting magnetically dominated (Poynting) jet, accelerated by magnetic pressure within the low-density polar cavity, is distinct from the denser, slower disk wind launched through the classic magnetic tower mechanism. Comparison with a disk-only model shows that the rotating stellar magnetosphere promotesbipolarjet launching by shaping a magnetic geometry favorable to symmetric outflows. 

Phonons, quantized vibrations of the atomic lattice, are central to thermal transport, structural stability, and phase behavior in crystalline solids. However, most large‐scale materials databases rely on the harmonic approximation and neglect important temperature‐dependent anharmonic effects. Here, we present a scalable framework combining machine learning interatomic potentials, anharmonic lattice dynamics, and high‐throughput calculations to predict finite‐temperature phonons across thousands of materials. By fine‐tuning the universal M3GNet potential with high‐quality phonon data, we improve phonon prediction accuracy fourfold while retaining computational efficiency. We integrate this refined model with a high‐throughput implementation of the stochastic self‐consistent harmonic approximation to compute temperature‐dependent phonons for 4669 inorganic compounds. The resulting dataset reveals systematic elemental and structural trends in anharmonic phonon renormalization, especially in alkali metals, perovskite‐derived frameworks, and related systems. Machine learning analysis identifies weak bonding, large atomic radii, and specific coordination motifs as key drivers of strong anharmonicity. First‐principles validation further shows that anharmonic effects can change lattice thermal conductivity by factors of two to four. This work provides an efficient data‐driven platform for predicting finite‐temperature phonon behavior and guiding the discovery of materials with tailored thermal and vibrational properties. 

The search for new functional materials with tunable properties remains a central challenge in chemistry, particularly for applications in energy and electronics. In this work, we present a framework for predictive crystal design in alkali metal chalcogenides that enables controlled dimensional reduction of a parent covalent motif, yielding a broad range of electronic structures, which systematically evolve from one parent to the other. We present 11 new members of the AnCu4–nSnS4 family (A = alkali metal; n = 0–4), which reduce the three-dimensional (3D) covalent network of Cu4SnS4 into various 3D, 2D, 1D, and 0D [Cu4–nSnS4]n− motifs through the substitution of Cu with alkali metals of various radii. The end members of the family set the range in achievable band gaps at 0.99 eV for fully covalent Cu4SnS4 (n = 0) and 3.38 eV for K4SnS4 (n = 4) with 0D [SnS4]n− tetrahedra. As the dimensionality of [Cu4–nSnS4]n− systematically reduces within AnCu4–nSnS4 (n = 1–3), a stepwise increase in band gap energy occurs through a gradual decrease in the energy of the valence band maximum and an increase in the conduction band minimum, with an increase in the effective masses of charge carriers. Furthermore, irrespective of the alkali metal, the thermal stability decreases with decreasing [Cu4–nSnS4]n− dimensionality within the quaternary members. Most importantly, we demonstrate that predictable crystal structure and property evolution for a given composition space is possible by deriving a general formula based on substituting the covalent metals of a parent structure with alkali metals. 

Abstract We analyze the dense gas kinematics in two class 0/I protostellar cores, Per 30 and NGC 1333 IRAS 7, in the Perseus Molecular Cloud to determine whether their velocity structures are indicative of rotation. We examine the hyperfine structure of the N₂H⁺J= 1–0 transition by combining 3″ (900 au) Atacama Large Millimeter/submillimeter Array measurements with 9″ (2700 au) measurements from the Green Bank Telescope. We use theCASA Feathermethod to combine these data in order to maximize our sensitivity across spatial scales. We fit the N₂H⁺spectra to constrain the centroid velocity of the gas at each pixel and use these values to calculate the linear velocity gradient and specific angular momentum within apertures centered on each protostar with radii ranging from 5″ to 60″. Our results indicate that the velocity structure probed by the N₂H⁺emission is likely not a result of core rotation. These findings are consistent with other studies in the literature that indicate rotation is often not evident on scales ≲1000 au. We instead suggest that the velocity structure we see is a result of torques caused by irregular density distributions in these protostellar systems.